Knowledge is a combination of theory and practice. Theory is understanding the process but without the practical (hands-on) experience. Years of knowledge is a valuable contributor to becoming an expert. This is often why, when an expert within your company leaves, the knowledge goes with them and this can leave a void of knowledge within your organisation.
It is important to read the datasheets, technical specification, attend product presentations and workshops but what you also really need to know is not always found on datasheets. It’s held in the mind of the expert, who has worked for 40+ years within the industry, travelled worldwide from site to site, been the “go to” colleague in a company and the person where the buck stops. Give ourselves 40 years within the industry and we too will have this knowledge, but what if you need the answers today?
I would recommend you sit down with your expert and ask them this important question. “What important, and at times career saving information, do we need which we won’t find written down anywhere?” This is what we recently asked Richard Packman who is the leading Tank Cleaning expert in the UK. The knowledge the team received was amazing and invaluable. Unfortunately, there will be unavoidable issues but by ensuring the knowledge is passed on within your organisation will certainly help eliminate the avoidable issues.
inTank Technologies are currently promoting their “Lunch and Learn” sessions with Richard Packman on Tank Cleaning /CIP. This is based at your premises and open to Engineers interested in fast tracking their knowledge and understanding all aspects of Tank Cleaning /CIP. This is an ideal time to have all your questions and more answered.
Below are some of the facts you won’t find on datasheets regarding Tank Cleaning. This list is being regularly updated, so please look out for more facts that might just be the career saving information you need to know today.
- If you supply both fixed spray and rotary spray heads with more than 2 bar pressure you are over pressurising them, wasting water and reducing the heads cleaning performance
- Modern detergents no longer need to be used at Ultra hot temperatures of 80- 85c , with temperatures of between 50 – 70°c now commonly being used.
- The presents of a CO2 atmosphere will rapidity deplete the strength of the typical 2% caustic solution turning it into unusable Sodium Carbonate.
- Available operational CIP fluid pressure should always be monitored at the top of the tank and not at the Pump/floor level. Pressure drop caused by the additional height of the tank and frictional loses generated by the pipework will not be taken into account.
- Frictional losses are generated by the cleaning fluid passing through the CIP supply pipework, valves. Bends and Tee’s etc. If the pipework is too small for the flow rate passing through it, the fluid velocity will be too high causing large frictional losses and the supply pump will not be able to achieve its required performance.
- Always use the minimum flow rate requirement calculations/curves before you choose a cleaning head just to pass the available flow rate, the actual requirement may be very much lower.
- An orifice plate is commonly used to lower the supply pressure to a fixed or rotary spray head from a high-pressure common header (supply feed). For example, the vessel may be being cleaned by a rotary jet head operating at 5 bar but the vessel is also using fixed spray balls to clean Vent Lines or a Manway etc which only require 2 bar. The orifice plate allows both cleaning heads to operate at their optimal pressure. The orifice plate is a very cost-effective solution.
- Excess pressure can cause the cleaning heads spray pattern to atomise. This is a big negative as it causes the CIP fluid consumption to increase whilst reducing the heads cleaning performance.
- It is never good practice for vessels to pond during the CIP process unless this is the only option to clean the underside of the lowest Agitator Blade or if used as a buffer for a simple recirculated CIP process , although during the final rinse cycle there must not be any ponding what so ever.
- Never use a stainless steel rotary spray head with high pressure steam or in a WFI Storage Vessel where the Ring Main recirculates the water 24 hours a day, both have poor lubrication performance.
- Always use a Pressure Gauge positioned in the CIP supply pipe work at the top of the vessel to achieve a full understanding of the cleaning fluid supply and the true operational performance of the cleaning head technology
- It is standard practice that all cleaning head technology should be removed, checked for trapped foreign bodies and cleaned at least every 6 months as they act as very good Filters.
- It is always advisable to install a good capacity fine mesh filter in the CIP supply pipe work from the CIP set to protect the cleaning head technology
- Pressure Gauges can be fitted either before or after a Filter to confirm to the process team when it becomes blocked.
- Be careful regarding shadowing inside a vessel, Agitators, Baffles, internal J Pipes and Ladders will all create shadows and care has to be taken to position the clean heads in the correct orientation especially when it comes to four equally spaced Baffles. (position the Baffles correctly for the heads as there maybe few choices for head position with a busy top dish layout.
- If the vessel has to pass a Riboflavin coverage test during FAT, huge care has to be taken at the point of cleaning head choice and inlet connection positioning, normally this is where specially targeted thick walled fixed spray balls are used to guarantee passing Riboflavin testing.
- Increasing demands on CIP Performance and efficiency to clean the most challenging areas within a vessel such as the undersides of either centre or off centre mounted Agitator Blades, this can now be achieved with 100% cleaning guarantees given, which is a true first for optimal CIP Performance.
- To truly optimise any CIP process we have to maximise the coverage and impact performance of the jets that are delivering the cleaning fluid across the internal surfaces of the vessel, maximising the coverage enables us to minimise water, chemical usage, cleaning time.
- To achieve the ultimate in optimised Vessel cleaning performance we have to use Simulation technology to enable us to optimise the three key parameters to cleaning any process vessel, Wetting Intensity in L/m² ( wetting coverage ), Pattern Mesh Width in mm ( cleaning pattern density ) and finally Transversal Speed ( jet coverage speed ) in m/second.